Light-sensitive material containing silver halide, a disulfonamido reducing agent and polymerizable compound

ABSTRACT

A light-sensitive material comprises a support and a light-sensitive layer containing silver halide, a polymerizable compound and a hydrazine derivative. The light-sensitive layer further contains a reducing agent having the following formula (I): ##STR1## in which each of Ar 1  and Ar 2  independently is an aryl group; and each of R 1 , R 2  and R 3  independently is a monovalent group such as hydrogen, a halogen atom, an alkyl group, a cycloalkyl, group, an aralkyl group, an aryl group, an alkenyl group, an alkynyl group, a heterocyclic group, an alkoxy group, an alkylthio group and an acylamino group.

FIELD OF THE INVENTION

This invention relates to a light-sensitive material comprising alight-sensitive layer containing silver halide, a reducing agent and apolymerizable compound provided on a support.

BACKGROUND OF THE INVENTION

Light-sensitive materials comprising a light-sensitive layer containingsilver halide, a reducing agent and a polymerizable compound provided ona support can be used in an image forming method in which a latent imageof silver halide is formed, and then the polymerizable compound ispolymerized to form the corresponding image.

Examples of said image forming methods are described in Japanese PatentPublication Nos. 45(1970)-11149 (corresponding to U.S. Pat. No.3,697,275), 47(1972)-20741 (corresponding to U.S. Pat. No. 3,687,667)and 49(1974)-10697, and Japanese Patent Provisional Publication Nos.57(1982)-138632, 57(1982)-142638, 57(1982)-176033, 57(1982)-211146(corresponding to U.S. Pat. No. 4,557,997), 58(1983)-107529(corresponding to U.S. Pat. No. 4,560,637), 58(1983)-121031(corresponding to U.S. Pat. No. 4,547,450) and 58(1983)-169143. In theseimage forming methods, when the exposed silver halide is developed usinga developing solution, the polymerizable compound is induced topolymerize in the presence of a reducing agent (which is oxidized) toform a polymer image. Thus, these methods need a wet development processemploying a developing solution. Therefore the process takes arelatively long time.

An improved image forming method employing a dry process is described inJapanese Patent Provisional Publication Nos. 61(1986)-69062 and61(1986)-73145 (the contents of both publications are described in U.S.Pat. No. 4,629,676). In this image forming method, a recording material(i.e., light-sensitive material) comprising a light-sensitive layercontaining a light-sensitive silver salt (i.e., silver halide), areducing agent, a cross-linkable compound (i.e., polymerizable compound)and a binder provided on a support is imagewise exposed to form a latentimage, and then the material is heated to polymerize within the areawhere the latent image of the silver halide has been formed. The abovemethod employing the dry process and the light-sensitive materialemployable for such method are also described in Japanese PatentProvisional Publication Nos. 61(1986)-183640, 61(1986)-188535 and61(1986)-228441.

Japanese Patent Provisional Publication No. 61(1986)-188535 describes animage forming method employing a hydrazine derivative (one of thereducing agents) in combination of another reducing agent. The methodhas an advantage of high sensitivity, compared with a method employingone kind of the reducing agent. Further, the method has anotheradvantage of accelerating the polymerization reaction, so that arelatively clear image can be obtained.

SUMMARY OF THE INVENTION

An object of the present invention is to provide a light-sensitivematerial which gives an improved clear image.

There is provided by the present invention a light-sensitive materialcomprising a support and a light-sensitive layer containing silverhalide, a polymerizable compound and a hydrazine derivative,characterized in that the light-sensitive layer further contains areducing agent having the following formula (I): ##STR2## in which eachof Ar¹ and Ar² independently is an aryl group, which may have one ormore substituent groups; and each of R¹, R² and R³ independently is amonovalent group selected from the group consisting of hydrogen, ahalogen atom, an alkyl group, a cycloalkyl group, an aralkyl group, anaryl group, an alkenyl group, an alkynyl group, a heterocyclic group, analkoxy group, an alkylthio group and an acylamino group, each of which(except hydrogen and the halogen atom) may have one or more substituentgroups.

The light-sensitive material of the invention is characterized by theuse of a specific reducing agent having the formula (I).

According to study of the present inventors, the compound having theformula (I) can be advantageously used as the reducing agent in thelight-sensitive material.

In more detail, the present inventors have found that the reducing agenthaving the formula (I) shows a strong reducing power when it is used incombination with a hydrazine derivative in a light-sensitive material.Accordingly, the polymerization reaction much accelerates when thereducing agent is used. Therefore, the light-sensitive material of theinvention has very high sensitivity and gives an improved clear image.

A strong reducing agent is generally unstable. For example, a strongreducing agent tends to be oxidized by oxygen in the air or an oxidizingsubstance contained in the light-sensitive layer (e.g., silver halide),when the light-senitive material is prepared or preserved. However, thereducing agent having the formula (I) shows the strong reducing poweronly in an image forming process. Therefore, the light-sensitivematerial of the invention can give a clear image, even if the materialis preserved for a long term.

The reducing agent shows the strong reducing power especially in a heatdevelopment process. Therefore, the light-sensitive material of theinvention can be advantageously used in a method employing a heatdevelopment process.

DETAILED DESCRIPTION OF THE INVENTION

The reducing agent employed in the present invention has the followingformula (I): ##STR3##

In the formula (I), each of Ar¹ and Ar² independently is an aryl group.Examples of the aryl group include phenyl, naphthyl and anthryl. Amongthem, phenyl is preferred.

The aryl group may have one or more substitutent groups. Examples of thesubstituent groups include a halogen atom, hydroxyl, cyano, amino, anacyl group, an alkylsulfonyl group, an arylsulfonyl group, an alkoxygroup, an aryloxy group, an alkylamino group, an arylamino group, analkylsulfamoyl group, an arylsulfamoyl group, an alkylcarbamoyl group,an arylcarbamoyl group, an alkoxycarbonyl group, an acylamino group, anacyloxy group, an alkylsulfonylamino group, an arylsulfonylamino group,an alkylthio group, an arylthio group and an alkyl group. Among them, analkyl group, a halogen atom, an alkoxy group, an alkylamino group, anacylamino group, an alkylsulfonylamino group, an alkylsulfamoyl groupand alkylcarbamoyl group are preferred. Each of the substituent grouppreferably contains 1-40 carbon atoms, and more preferably contains 1-25carbon atoms.

Examples of the halogen atom include fluorine, chlorine, bromine andiodine. Examples of the acyl group include acetyl, benzoyl, octanoyl anddodecanoyl. An example of the alkylsulfonyl group is methylsulfonyl. Anexaple of the arylsulfonyl group is phenylsulfonyl. Examples of thealkoxy group include methoxy, ethoxy, isopropoxy, octyloxy, dodecyloxyand benzyloxy. An example of the aryloxy group is phenoxy. Examples ofthe alkylamino group include dimethylamino, dibutylamino, dibenzylamino,methylamino and butylamino. An example of the arylamino group isdiphenylamino. Examples of the alkylsulfamoyl group includedibutylsulfamoyl and dibenzylsulfamoyl. An example of the arylsulfamoylgroup is diphenylsulfamoyl. Examples of the alkylcarbamoyl group includedibutylcarbamoyl, diphenylcarbamoyl and dibenzylcarbamoyl. An example ofthe arylcarbamoyl group is diphenylcarbamoyl. Examples of thealkoxycarbonyl group include butoxycarbonyl, dodecyloxycarbonyl andbenzyloxycarbonyl. Examples of the acylamino group include butyrylamino,dodecanoylamino, N-methylbenzoylamino and phenylacetylamino. Examples ofthe acyloxy group include dodecyloxy, benzoyloxy and phenylacetoxy. Anexample of the alkylsulfonylamino group is dodecylsulfonylamino.Examples of the arylsulfonylamino group include toluenesulfonylamino andphenylsulfonylamino. Examples of the alkylthio group include octylthio,dodecylthio and benzylthio. An example of the arylthio group isphenylthio. Examples of the alkyl group include methyl, ethyl, butyl,octyl, dodecyl and benzyl.

Each of R¹, R² and R³ independently is a monovalent group selected fromthe group consisting of hydrogen, a halogen atom, an alkyl group, acycloalkyl group, an aralkyl group, an aryl group, an alkenyl group, analkynyl group, a heterocyclic group, an alkoxy group, an alkylthio groupand an acylamino group, each of which (except hydrogen and the halogenatom) may have one or more substituent groups. Hydrogen, a halogen atom,an alkyl group and an acylamino group are preferred. Each of R¹, R² andR³ preferably contains not more than 20 carbon atoms, and morepreferably not more than 6 carbon atoms. It is most preferred that eachof R¹, R² and R³ is hydrogen, because such compound having hydrogens forR¹, R² and R³ can be easily synthesized at a relatively low cost.Examples of the groups are similar to those of the substituent groups of"Ar".

Concrete examples of the reducing agent employable for the presentinvention are described hereinbelow without limiting the invention.##STR4##

The above-mentioned reducing agents used in the present invention areknown compounds or derivatives thereof. Therefore, the reducing agentscan be synthesized by a known manner. Japanese Patent ProvisionalPublication No. 59(1984)-5247 describes that the reducing agent can beused as a trapping agent for oxidation product of a developing agent.Japanese Patent Provisional Publications No. 60(1985)-198540 and No.60(1985)-227255 describe that a similar compound can be used as anantifogging agent in the heat developable light-sensitive material.

The reducing agent of the present invention is used as a reducing agent(developing agent) in the image forming method employing apolymerization reaction initiated by silver halide. Therefore, use ofthe reducing agent is completely different from those of thePublications.

The reducing agent can be added to the light-sensitive layer in theamount of 0.1 to 1,500 mole % based on the amount of silver (containedin the silver halide and an organic silver salt), and more preferably 10to 300 mole %.

In the light-sensitive material of the invention, the reducing agent isused in combination with a hydrazine derivative. There is no specificlimitation with respect to the hydrazine derivative. However, it ispreferred that the hydrazine derivative is a compound having thefollowing formula (II) or (III): ##STR5##

In the formula (II), R⁴ is a monovalent group selected from the groupconsisting of hydrogen, an alkyl group, an aralkyl group, a cycloalkylgroup, an aryl group and a heterocyclic group, each of which may haveone or more substituent groups such as a halogen atom, an alkyl group,amino, nitro, cyano, an alkylamino group, an arylamino group and anacylamino group; R⁵ is a monovalent group selected from the groupconsisting of an alkyl group, a halogen atom, an acylamino group, analkoxy group and hydroxyl; and n is 0, 1, 2, 3, 4 or 5.

It is preferred that R⁴ is a monovalent group selected from the groupconsisting of hydrogen, an alkyl group and and aryl group. R⁴ preferablycontains not more than 20 carbon atoms, and more preferably not morethan 6 carbon atoms.

Examples of the alkyl group which can constitute R⁴ include methyl,ethyl, hexyl, octyl and 2-ethylhexyl. An example of the aralkyl group isbenzyl. Examples of the cycloalkyl group include cyclopentyl andcyclohexyl. Examples of the aryl group include phenyl and naphtyl.Examples of the heterocyclic group include pyridyl, quinolyl, thienyland furyl.

It is preferred that the substituent group of R⁴ is a halogen atom or analkyl group.

Examples of the halogen atoms which can constitute the substituent groupof R⁴ include fluorine, chlorine, bromine and iodine. Examples of thealkyl group include methyl, ethyl, t-amyl and t-octyl. Examples of thealkylamino group include methylamino, dimethylamino, dibutylamino anddibenzylamino. An example of the arylamino group is diphenylamino.Examples of the acylamino group include acethylamino, butyrylamino andbenzoylamino.

Examples of the alkyl group which can constitute R⁵ include methyl andbutyl. Examples of the halogen atoms include fluorine, chlorine, bromineand iodine. Examples of the acylamino group include2-ethylhexanoylamino, benzoylamino and phenoxyacetylamino group.Examples of the alkoxy group include methoxy, butoxy, phenoxy andbenzyloxy.

R⁵ may be placed at any of o-, m- and p-position. When "n" is two ormore, the groups represented by R⁵ may be different from each other.##STR6##

In the formula (III), R⁶ is a monovalent group selected from the groupconsisting of hydroxyl, an alkoxy group, amino, an alkylamino group andan arylamino group; and m is 0, 1, 2, 3, 4 or 5.

Examples of the alkoxy group which can constitute R⁶ include methoxy,buthoxy, phenoxy, 2-ethylhexyloxy and benzyloxy. Examples of thealkylamino group include dimethylamino, diethylamino, dibutylamino anddibenzylamino. An example of the arylamino group is diphenylamino.

R⁶ may be placed at any of o-, m- and p-position. When "m" is two ormore, the groups represented by R⁶ may be different from each other.

The hydrazine derivative is preferably used in an amount of 0.1 to 20mole based on the amount of silver.

The hydrazine derivative can be used singly or in combination with otherhydrazine derivative.

Examples of the hydrazine derivatives which are preferably used in theinvention are described hereinafter. ##STR7##

The silver halide, the polymerizable compound and the support whichconstitute the light-sensitive material of the invention in addition tothe reducing agent and the hydrazine derivative are described below.Thus composed material is referred hereinafter to as "light-sensitivematerial".

There is no specific limitation with respect to silver halide containedin the light-sensitive layer of the light-sensitive material.

Examples of the silver halides employable in the light-sensitivematerial of the invention include silver chloride, silver bromide,silver iodide, silver chlorobromide, silver chloroiodide, silveriodobromide, and silver chloroiodobromide in the form of grains.

The halogen composition of individual grains may be homogeneous orheterogeneous. The heterogeneous grains having a multilayered structrein which the halogen composition varies from the core to the outer shell(see Japanese Patent Provisional Publications Nos. 57(1982)-154232,58(1983)-108533, 59(1984)-48755 and 59(1984)-52237, U.S. Pat. No.4,433,048, and European Patent No. 100,984) can be employed. A silverhalide grain having a core/shell structure in which the silver iodidecontent in the shell is higher than that in the core can be alsoemployed.

There is no specific limitation on the crystal habit of silver halidegrains. For example, a tubular grain having an aspect ratio of not lessthan 3 can be also employed.

The silver halide grains preferably have such a relatively low tendencyto be fogged that the amount of developed silver is not more than 5weight % based on the total amount of silver when the unexposed silverhalide grains are developed in 1 l of an agueous developing solutioncontaining 1.0 g of metol, 15.0 g of sodium sulfite, 4.0 g ofhydroquinone, 26.7 g of sodium carbonate monohydrate and 0.7 g ofpotassium bromide.

Two or more kinds of silver halide grains which differ in halogencomposition, crystal habit, grain size, and/or other features from eachother can be used in combination.

There is no specific limitation on grain size distribution of silverhalide grains. For example, the silver halide grains having such a grainsize distribution that the coefficient of the variation is not more than20% can be employed.

The silver halide grains ordinarily have a mean size of 0.001 to 5 μm,more preferably 0.001 to 2 μm.

The total silver content (including silver halide and an orgainc silversalt which is one of optional components) in the light-sensitve layerpreferably is in the range of frrom 0.1 mg/m² to 10 g/m². The silvercontent of the silver halide in the light-sensitive layer preferably isnot more than 0.1 g/m², more preferably in the range of from 1 mg/m² to90 mg/m².

There is no specific limitation with respect to the polymerizablecompound, and any known polymerizable compounds including monomers,oligomers and polymers can be contained in the light-sensitive layer. Inthe case that heat development (i.e., thermal development) is utilizedfor developing the light-sensitve material, the polymerizable compoundshaving a relatively higher boiling point (e.g., 80° C. or higher) thatare hardly evaporated upon heating are preferably employed. In the casethat the light-sensitive layer contains a color image forming substance,the polymerizable compounds are preferably cross-linkable compoundshaving plural polymerizable groups in the molecule, because suchcross-linkable compounds favorably serve for fixing the color imageforming substance in the course of polymerization hardening of thepolymerizable compounds.

The polymerizable compound employable for the light-sensitive materialof the invention are described in the above-mentioned andlater-mentioned publications and applications concerning thelight-sensitive material.

Preferred polymerizable compounds employable for the light-sensitivematerial are compounds which are polymerizable through addition reactionor ring-opening reaction. Preferred examples of the compounds beingpolymerizable through addition reaction include compounds having anethylenic unsaturated group. Preferred examples of the compounds beingpolymerizable through ring-opening reaction include the compounds havingan epoxy group. Among them, the compounds having an ethylenicunsaturated group are preferred.

Examples of compounds having an ethylenic unsaturated group includeacrylic acid, salts of acrylic acid, acrylic esters, acrylamindes,methacrylic acid, salts of methacrylic acid, methacrylic esters,methacrylamide, maleic anhydride, maleic esters, itaconic esters,styrene, styrene derivatives, vinyl ethers, vinyl esters, N-vinylheterocyclic compounds, allyl ethers, allyl esters, and compoundscarrying a group or groups corresponding to one or more of thesecompounds.

Concrete examples of the acrylic esters include n-butyl acrylate,cyclohexyl acrylate, 2-ethylhexyl acrylate, benzyl acrylate, furfurylacrylate, ethoxyethoxy acrylate, dicyclohexyloxyethyl acrylate,nonylphenyloxyethyl acrylate, hexanediol diacrylate, butanedioldiacrylate, neopentylglycol diacrylate, trimethylolpropane triacrylate,pentaerythritol tetraacrylate, dipentaerythritol pentaacrylate,diacrylate of polyoxyethylenated bisphenol A, polyacrylate ofhydroxypolyether, polyester acrylate, and polyurethane acrylate.

Concrete examples of the methacrylic esters include methyl methacrylate,butyl methacrylate, ethylene glycol dimethacrylate, butanedioldimethacrylate, neopentylglycol dimethacrylate, trimethylolpropanetrimethacrylate, pentaerythritol trimethacrylate, pentaerythritoltetramethacrylate, and dimethacrylate of polyoxyalkylenated bisphenol A.

The polymerizable compounds can be used singly or in combination of twoor more compounds. For example, a mixture of two or more polymerizablecompounds can be employed. Further, compounds formed by bonding apolymerizable group such as a vinyl group or a vinylidene group to areducing agent or a color image forming substance are also employed asthe polymerizable compounds. The light-sensitive materials employingthese compounds which show functions as both the reducing agent and thepolymerizable compound, or of the color image forming substance and thepolyerizable compound are included in embodiments of the invention.

The amount of the polymerizable compound for incorporation into thelight-sensitive layer preferably ranges from 5 to 1.2×10⁵ times (byweight) as much as the amount of silver halide, more preferably from 10to 1×10⁴ times as much as the silver halide.

There is no specific limitation with respect to the color image formingsubstance, and various kinds of substances can be employed. Thus,examples of the color image forming sustance include both coloredsubstance (i.e., dyes and pigments) and non-colored or almostnon-colored substance (i.e., color former or dye- or pigment-precursor)which develops to give a color under application of external energy(e.g., heating, pressing, light irradiation, etc. ) or by contact withother componets (i.e., developer). The light-sensitve material using thecolor image forming substance is decribed in Japanese Patent ProvisionalPublicaiton No. 61(1986)-73145.

Examples of the dyes and pigments (i.e., colored substances) employablein the invention include commercially available ones, as well as variousknown compounds described in the technical publications, e.g., YukiGosei Kagaku Kyokai (ed.), Handbook of Dyes (in Japanese, 1970) andNippon Ganryo Gijutsu Kyokai (ed.), New Handbook of Pigments (inJapanese, 1977). These dyes and pigments can be used in the form of asolution or a dispersion.

Examples of the substances which develop to give a color by certainenergy includes thermochromic compounds, piezochromic compounds,photochromic compounds and leuco compounds derived from triarylmethanedyes, quinone dyes, indigoid dyes, azine dyes, etc. These compounds arecapable of developing a color by heating, application of pressure,light-irradiation or air-oxidation.

Examples of the substances which develop to give a color in contact withother components include various compounds capable of developing a colorthrough some reaction between two or more components, such as acid-basereaction, oxidation-reduction reaction, coupling reaction, chelatingreaction, and the like. Examples of such color formation systems aredescribed in Hiroyuki Moriga, "Introduction of Chemistry of SpecialityPaper" (in Japanese, 1975), pp. 29-58 (pressure-sensitve copying paper),pp. 87-95 (axo-graphy), pp. 118-120 (heat-sensitive color formation by achemical change) or in MSS. of the seminer promoted by the Society ofKinki Chemical Industry, "The Newest Chemistry of ColoringMatter--Attractive Application and New Development as a FunctionalColoring Matter", pp. 26-32 (Jun. 19, 1980). Examples of the colorformation systems specifically include a color formation system used inpressure-sensitive papers, etc., comprising a color former having apartial structure of lactone, lactam, spiropyran, etc., and an acidicsubstance (developer), e.g., acid clay, phenol, etc.; a system utilizingazo-coupling reaction between an aromatic a diazonium salt, diazotate ordiazosulfonate and naphthol, aniline, active methylene, etc.; a systemutilizing a chelating reaction, such as a reaction betweenhexamethylenetetramine and a ferric ion and gallic acid, or a reactionbetween a phenolphthalein-complexon and an alkaline earth metal ion; asystem utilizing oxidation-reduction reaction, such as a reactionbetween ferric stearate and pyrogallol, or a reaction between silverbehenate and 4-methoxy-1-naphthol, etc.

The color image forming substance in the light-sensitive material ispreferably used in an amount of from 0.5 to 50 parts by weight, and morepreferably from 2 to 30 parts by weight, per 100 parts by weight of thepolymerizable compound. In the case that the developer is used, it ispreferably used in an amount of from about 0.3 to about 80 parts byweight per one part by weight of the color former.

In the case that the color image forming substance comprises twocomponents (e.g., color former and a developer), one component and thepolymerizable compound is contained in the microcapsule, and the othercomponent is arranged outside of the microcapsule in the light-sensitivelayer, a color image can be formed on the light-sensitive layer.

The light-sensitive material can be prepared by arranging alight-sensitive layer containing the above-mentioned components on asupport. There is no limitation with respect to the support. In the casethat a heat development is unilized in the use of the light-sensitivematerial, the support preferably is resistant to heat given in theprocessing stage. Examples of the material employable as the supportinclude glass, paper, fine paper, coat paper, cast-coated paper, barytapaper, synthetic paper, metals and analogues thereof, polyester, acetylcellulose, cellulose ester, polyvinyl acetal, polystyrene,polycarbonate, polyethylene terephthalate, and paper laminated withresin or polymer (e.g., polyethylene). In the case that a porousmaterial, such as paper is employed as the support, the porous supportpreferably has such a surface characteristic that a filtered maximumwaviness of not less than 4 μm is observed in not more than 20 positionsamong 100 positions which are determined at random on a filteredwaviness curve obtained according to JIS-B-0610. A surface of a papersupport preferably has a low water absorptiveness of not more than 3g/m² which is a value measured according to Cobb test method. A surfaceof the paper support preferably has such a smooth surface that thesmoothness value in terms of the Bekk Smoothness is not less than 300seconds. A paper support preferably has a low shrinkage ratio of notmore than 0.15% both in the machine direction and in the crossdirection, wherein the shrinkage ratio is a value measured at the changeof relative humidity form 75% to 60%. Further, a paper supportpreferably has a low air permeability of not less than 300 seconds,wherein the air permeability is a time required for 100 ml of air topass through the paper support of an area of 645 mm² at pressure of 567g. Furthermore, a paper support preferably has a pH value in the rangeof 5 to 9.

Various embodiments of the light-sensitive materials, optionalcomponents which may be contained in the light-sensitive layer, andauxiliary layers which may be optionally arranged on the light-sensitivematerials are described below.

In the light-sensitive material of the invention, the polymerizablecompound is preferably dispersed in the form of oil droplets in thelight-sensitive layer. Other components in the light-sensitive layer,such as silver halide, the reducing agent (hereinafter including thehydrazine derivative), the color image forming substance may be alsocontained in the oil droplets.

In the case that silver halide grains are contained in the oil droplets,the oil droplets containing five or more silver halide grains arepreferably more than 50% by weight.

The oil droplets of the polymerizable compound are preferably in theform of microcapsules. There is no specific limitation on preparation ofmicrocapsules.

There is also no specific limitation on shell material of themicrocapsule, and various known materials such as polymers which areemployed in the conventional microcapsules can be employed as the shellmaterial. Examples of the shell material include polyamide resin and/orpolyester resin, polyurea resin and/or polyurethane resin, aminoaldehyderesin, gelatin, epoxy resin, a complex resin containing polyamide resinand polyurea resin, a complex resin containing polyurethane resin andpolyester resin.

The mean size of the microcapsule preferably ranges from 0.5 to 50 μm,more preferably 1 to 25 μm, most preferably 3 to 20 μm.

In the case that silver halide grains are contained in the microcapsule,the silver halide grains are preferably arranged in the shell materialof the microcapsules.

Further, two or more kinds of the microcapsules differing from eachother with respect to at least one of the silver halide, polymerizablecompound and color image forming substance can be employed. Furthermore,three or more kinds of the microcapsules differing from each other withrespect to the color image forming substance is preferably employed toform a full color image.

The light-sensitive layer can further contain optional components suchas sensitizing dyes, orgainc silver salts, radical generators, variouskinds of image formation accelerators, thermal polymerizationinhibitors, thermal polymerization initiators, development stoppingagents, fluorescent brightening agents, discoloration inhibitors,antihalation dyes or pigments, anti-irradiation dyes or pigments,matting agents, antismudging agents, plasticizers, water releasers,binders, photo polymerization initiator, solvent of the polymerizablecompound and water soluble vinyl polymers.

There is no specific limitation with respect to the sensitizing dyes,and known sensitizing dyes used in the conventional art of photographymay be employed in the light-sensitve material. Examples of thesensitizing dyes include methine dyes, cyanine dyes, merocyanine dyes,complex cyanine dyes, complex mercyanine dyes, holopolar cyanine dyes,hemicyanine dyes, styryl dyes, and hemioxonol dyes. These sensitizingdyes can be used singly or in combination. Combinations of sensitizingdyes are often used for the purpose of supersensitization. In additionto the sensitizing dyes, a substance which does not per se exhibitspectral sensitization effect or does not substantially absorb visiblelight but shows supersensitizing activity can be used. The amount of thesensitizing dye to be added generally ranges from about 10⁻⁸ to about10⁻² mol per 1 mol of silver halide, The sensitizing dye is preferablyadded during the stage of the preparation of the silver halide emulsion(simultaneously with or after the grain formation).

The sensitizing dye is preferably added during the stage of thepreparation of the silver halide emulsion.

In the heat-development process, an organic silver salt is preferablycontained in the light-sensitive material. It can be assumed that theorganic silver salt takes part in a redox reaction using a silver halidelatent image as a catalyst when heated to a temperature of 80° C. orhigher. In such case, the silver halide and the organic silver saltpreferably are located in contact with each other or close together.Examples of orgainc compounds employable for forming such organic silversalt include aliphatic or aromatic carboxylic acids, thiocarbonylgroup-containing compounds having a mercapto group or an α-hydrogenatom, imino group-containing compounds, and the like. Among them,benzotriazoles are most preferable. The organic silver salt ispreferably used in an amount of from 0.01 to 10 mol., and preferablyfrom 0.01 to 1 mol., per 1 mol. of the light-sensitive silver halide.Instead of the organic silver salt, an organic compound (e.g.,benzotriazole) which cna form an organic silver salt in combination withan inoganic silver salt can be added to the light-sensitive layer toobtain the same effect.

Examples of the radical generators include triazene-silver, silverdiazotate and an azo compound.

Various image formation accelerators are employable in thelight-sensitive material. The image formation accelerators have afunction to accelerate the oxidation-reduction reaction between a silverhalide (and/or an organic silver salt) and a reducing agent, a functionto accelerate emigration of an image forming substance from alight-sensitive layer to an image-receiving material or animage-receiving layer, or a similar function. The image formationaccelerators can be classified into bases, base precursors, oils,surface active agents, compounds functioning as an antifogging agentand/or a development accelerator, hot-melt solvents, antioxidants andthe like. These groups, however, generally have certain combinedfunctions, i.e., two or more of the above-mentioned effects. Thus, theabove classification is for the sake of convenience, and one compoundoften has a plurality of functions combined.

Various examples of these image formation accelerators are shown below.

Preferred examples of the inorganic bases include hydroxides of alkalimetals or alkaline earth metals; secondary or tertiary phosphates,borates, corbonates, quinolinates and metaborates of alkali metals oralkaline earth metals; a combination of zinc hydroxide or zinc oxide anda chelating agent (e.g., sodium picolinate); ammonium hydroxide;hydroxides of quaternary alkylammoniums; and hydroxides of other metals.Preferred examples of the organic bases include aliphatic amines (e.g.,trialkylamines, hydroxylamines and aliphatic polyamines); aromaticamines (e.g., N-alkyl-substituted aromatic amines,N-hydroxylalkyl-substituted aromatic amines anddis[p-(dialkylamino)phenyl]-methanes), heterocyclic amines, amidines,cyclic amidines, guanidines, and cyclic guanidines. Of these bases,those having a pKa of 7 or more are preferred.

The base precursors preferably are those capable of releasing bases uponreaction by heating, such as salts between bases and organic acidscapable of decarboxylation by heating, compounds capable of releasingamines through intramolecular nucleophilic substitution, Lossenrearrangement, or Beckmann rearrangement, and the like; and thosecapable of releasing bases by electrolysis. Preferred exmaples of thebase precursors include guanidine trichloroacetate, piperidinetrichloroacetate, morpholine trichloroacetate, p-toluidinetrichloroacetate, 2-picoline trichloroacetate, guanidinephenylsulfonylacetate, guanidine 4 -chlorophenylsulfonylacetate,guanidine 4-methyl-sulfonylphenylsulfonylacetate, and 4-acetylaminomethyl propionate.

These bases or base precursors are preferably used in an amount of notmore than 100% by weight, and more preferably from 0.1 to 40% by weight,based on the total solid content of the light-sensitive layer. Thesebases or base precursors can be used singly or in combination.

In the light-sensitive material, the silver halide, the reducing agent,the polymerizable compound and the color image forming substance arepreferably contained in microcapsules and the base or base precursor ispreferably arranged outisde of the microcapsule in the light-sensitivelayer. Further, the base or base precursor can be contained in differentmicrocapsules from those containing the polymerizable compound. The baseor base precursor can be contained in the microcapsules under acondition that the base or base precursor is dissolved or dispersed inan aqueous solution of a water retention agent, or under a conditionthat the base or base precursor is adsorbed on solid particles. The baseor base precursor contained in the microcapsules preferably has amelting point in the range of 70° to 210° C.

The base or base precursor can be contained in a layer different fromthe light-sensitive layer. Further, the base or base precursor can becontained in a porous support.

Examples of the oils employable in the invention include high-boilingorganic solvents which are used as solvents in emulsifying anddispersing hydrophobic compounds.

Examples of the surface active agents employable in the inventioninclude pyridinium salts, ammonium salts and phosphonium salts asdescribed in Japanese Patent Provisional Publication No. 56(1984-74547;polyalkylene oxides as described in Japanese Patent ProvisionalPublication No. 59(1984) -57231.

The compounds functioning as an antifogging agent and/or a developmentaccelerator are used to give a clear image having a high maximum densityand a low minimum density (an image having high contrast). Examples ofthe compounds include a 5- or 6-membered nitrogen containingheterocyclic compound (e.g., a cyclic amide compound), a thioureaderivative, a thioether compound, a polyethylene glycol derivative, athiol derivative, an acetylene compound, a sulfonamide derivative and aquarternary ammonium salt.

The hot-melt solvents preferably are compounds which may be used assolvent of the reducing agent or those which have high dielectricconstant and can accelerate physical development of silver salts.Examples of the hot-melt solvents include polyethylene glycols,derivatives of polyethylene oxides (e.g., oleate ester), beeswax,monostearin and high dielectric constant compounds having --SO₂ --and/or --CO-- group described in U.S. Pat. No. 3,347,675; polarcompounds described in U.S. Pat. No. 3,667,959; and 1,10-decanediol,methyl anisate and biphenyl suberate described in Research Disclosurepp. 26-28 (Dec. 1976). The hot-melt solvent is preferably used in anamount of from 0.5 to 50% by weight, and more preferably from 1 to 20%by weight, based on the total solid content of the light-sensitve layer.

The antioxidants can be used to eliminate the influence of the oxygenwhich has an effect of inhibiting polymerization in the developmentprocess. An example of the antioxidants is a compound having two or moremercapto groups.

The thermal polymerization initiators employable in the light-sensitivematerial perferably are compounds that are decomposed under heating togenerate a polymerization initiating species, particularly a radical,and those commonly employed as initiators of racical polymerization. Thethermal polymerization initiators are described in "AdditionPolymerization and Ring Opening Polymerization", pp. 6-18edited by theEditorial Committee of High Polymer Experimental Study of the HighPolymer Institute, published by Kyoritsu Shuppan (1983). Examples of thethermal polymerization initiators include azo compounds, e.g.,azobisisobutyronitrile, 1,1'-azobis(1-cyclohexanecarbonitrile), dimethyl2,2'-azobisisobutyrate, 2,2'-azobis(2-methylbutyronitrile), andazobisdimethylvaleronitrile; organic peroxides, e.g., benzoyl peroxide,di-tert-butyl peroxide, dicumyl peroxide, tert-butyl hydroperoxide, andcumene hydroperoxide; inorganic peroxides, e.g., hydrogen peroxide,potassium persulfate, and ammonium persulfate; and sodiump-toluenesulfinate. The thermal polymerization initiators are preferablyused in an amount of from 0.1 to 120% by weight, and more preferablyfrom 1 to 10% by weight, based on amount of the polymerizable compound.In a system in which the polymerizable compound within the area wherethe latent image has not been formed is polymerized, the thermalpolymerization initiators are preferably incorporated into thelight-sensitive layer. The light-sensitive material employing thethermal polymerization initiators is described in Japanese PatentProvisional Publication No. 61(1986)-260241.

The development stopping agents employable in the light-sensitivematerial are compounds that neutralize a base or react with a base toreduce the base concentration in the layer to thereby stop development,or compounds that mutually react with silver or a silver salt tosuppress development. More specifically, examples of the developmentstopping agents include acid precursors capable of releasing acids uponheating, electrophilic compounds capable of undergoing substitutionreaction with a coexisting base upon heating, nitrogen-containingheterocyclic compounds, mercapto compounds, and the like. Examples ofthe acid precursors include oxide esters described in Japanese PatentProvisional Publication Nos. 60(1985)-108837 and 60(1985)-192939 andcompounds which release acids through Lossen rearrangement described inJapanese Patent Provisional Publication No. 60(1985)-230133. Examples ofthe electophilic compounds which induce substitution reaction with basesupon heating are described in Japanese Patent Provisional PublicationNo. 60(1985)-230134.

The dyes or pigments can be contained in the light-sensitive layer forthe purpose of anti-halation or anti-irradiation. Further, whitepigments can be contained in the light-sensitive layer for the purposeof anti-halation or anit-irradiation.

The dyes having a property of being decolorized when it is heated orirradiated with light can be used in the light-sensitive material as ayellow filter layer in a conventional silver salt photographic system.

The antismudging agents employable in the light-sensitive materialpreferably are particles which are solid at ambient temperatures.Examples of the antismudging agents include starch particles describedin U.K. Patent No. 1,232,347; polymer particles described in U.S. Pat.No. 3,625,736; microcapsule particles containing no color formerdescribed in U.K. Patent No. 1,235,991; and cellulose particles, andinorganic particles such as particles of talc, kaolin, bentonite,agalmatolite, zinc oxide, titanium dioxide or alumina described in U.S.Pat. No. 2,711,375. Such particles preferably have a means size of 3 to50 μm, more preferably 5 to 40 μm. When the microcapsule is employed inthe light-sensitive material, the size of said particle is preferablylarger than that of the microcapsule.

Binders employable in the light-sensitive material preferably aretransparent or semi-transparent hydrophilic binders. Examples of thebinders include natural substances, such as gelatin, gelatinderivatives, cellulose derivatives, starch, and gum arabic; andsynthetic polymeric substances, such as water soluble polyvinylcompounds e.g., polyvinyl alcohol, polyvinylpyrrolidone, and acrylamidepolymers. In addition to the synthetic polymeric substances, vinylcompounds dispersed in the form of latex, which are particularlyeffective to increase dimensional stability of photographic materials,can be also used. These binders can be used singly or in combination.The light-sensitive material employing a binder is described in JapanesePatent Provisional Publication No. 62(1986)-69062 (corresponding to U.S.Pat. No. 4,629,676 and European Patent Provisional Publication No.0174634A2).

In the case that the solvent of the polymerizable compound is used, thesolvent is preferably contained in a microcapsule which is differentfrom the light-sensitive microcapsule.

In the case that the water soluble vinyl polymer is used, the polymersare preferably adsorbed on the silver halide grains.

Examples and usage of the other optional components which can becontained in the light-sensitive layer are also described in theabove-mentioned publications and applications concerning thelight-sensitve material, and in Research Disclosure Vol. 170, No. 17029,pp. 9-15 (Jun. 1978).

Examples of auxiliary layers which are optionally arranged on thelight-sensitive mateiral include an image-receiving layer, a heatinglayer, an antistatic layer, an anticurl layer, a release layer, a coversheet or a protective layer and an antihalation layer (colored layer).

Instead of the use of the image-receiving material, the image-receivinglayer can be arranged on the light-sensitive material to produce thedesired image on the image-receiving layer of the light-sensitivematerial. The image-receiving layer of the light-sensitive material canbe constructed in the same manner as the layer of the image-receivinglayer. The details of the image-receiving layer will be described later.

Examples and usage of the other auxiliary layers are also described inthe above-mentioned publications and applications concerning thelight-sensitive material.

The light-sensitive material of the invention can be prepared, forinstance, by the folowing process.

The light-sensitive material is usually prepared by dissolving,emulsifying or dispersing each of the components of the light-sensitivelayer in an adequate medium to obtain coating solution, and then coatingthe obtained coating solution on a support.

The coating solution can be prepared by mixing liquid compositions eachcontaining a component of the light-sensitive layer. Liquid compositioncontaining two or more components may be also used in the preparation ofthe coating solution. Some components of the light-sensitive layer canbe directly added to the coating solution or the liquid composition.Further, a secondary composition can be prepared by emulsifiying theoily (or aqueous) composition in an aqueous (or oily) medium to obtainthe coating solution.

Preparations of liquid compositions and coating solutions of thecomponents contained in the light-sensitive layer are describedhereinbelow.

The silver halide is preferably prepared in the form of a silver halideemulsion. Various processes for the preparation of the silver halideemulsion are known in the conventional technology for the preparation ofphotographic materials.

The silver halide emulsion can be prepared by the acid process, neutralprocess or ammonia process. In the stage for the preparation, a solublesilver salt and a halogen salt can be reacted in accordance with thesingle jet process, double jet process or a combination thereof. Areverse mixing method, in which grains are formed in the presence ofexcess silver ions, or a controlled double jet process, in which a pAgvalue is maintained constant, can be employed. In order to accelerategrain growth, the concentrations or amounts or the silver salt andhalogen salt to be added or the rate of their addition can be increasedas described in Japanese Patent Provisional Publications Nos.55(1980)-142329 and 55(1980) -158124, and U.S. Pat. No. 3,650,757, etc.

The silver halide emulsion may be of a surface latent image type thatforms a latent image predominantly on the surface of silver halidegrains, or of an inner latent image type that forms a latent imagepredominantly in the interior of the grains. A direct reversal emulsioncomprising an inner latent image type emulsion and a nucleating agentmay be employed. The inner latent image type emulsion suitable for thispurpose is described in U.S. Pat. Nos. 2,592,250 and 3,761,276, JapanesePatent Publication No. 58(1983)-3534 and Japanese Patent ProvisionalPublication No. 57(1982)-136641, etc. The nucleating agent that ispreferably used in combination with the inner latent image type emulsionis described in U.S. Pat. Nos. 3,227,552, 4,245,037, 4,255,511,4,266,013 and 4,276,364, and West German Patent Provisional Publication(OLS) No. 2,635,316.

In the preparation of the silver halide emulsions, hydrophilic colloidsare advantageously used as protective colloids. Examples of usablehydrophilic colloids include proteins, e.g., gelatin, gelatinderivatives, gelatin grafted with other polymers, albumin, and casein;cellulose derivatives, e.g., hydroxyethyl cellulose, carboxymethylcellulose, cellulose sulfate, etc.; saccharide derivatives, e.g., sodiumalginate and starch derivative; and a wide variety of synthetichydrophilic polymers, such as polyvinyl alcohol, polyvinyl alcoholpartial acetal, poly-N-vinylpyrrolidone, polyacrylic acid,polymethacrylic acid, polyacrylamide, polyvinylimidazole, andpolyvinylpyrazole, and copolymers comprising monomers constituting thesehomopolymers. Among them, gelatin is most preferred. Examples ofemployable gelatins include not only lime-processed gelatin, but alsoacid-processed gelatin and enzyme-processed gelatin. Hydrolysis productsor enzymatic decomposition products of gelatin can also be used.

In the formation of silver halide grains in the silver halide emulsion,ammonia, an organic thioether derivative as described in Japanese PatentPublication No. 47(1972)-11386 or sulfur-containing compound asdescribed in Japanese Patent Provisional Publication No. 53(1978)-144319can be used as a silver halide solvent. Further, in the grain formationor physical ripening, a cadmium salt, a zinc salt, a lead salt, athallium salt, or the like can be introduced into the reaction system.Furthermore, for the purpose of overcoming high or low intensityreciprocity law failure, a water soluble iridium salt, e.g., iridium(III) or (IV) chloride, or ammonium hexachloroiridate, or a watersoluble rhodium salt, e.g., rhodium chloride can be used.

After the grain information or physical ripening, soluble salts may beremoved from the resulting emulsion by a known noodle washing method ora sedimentation method. The silver halide emulsion may be used in theprimitive condition, but is usually subjected to chemical sensitization.Chemical sensitization can be carried out by the sulfur sensitization,reduction sensitization or noble metal sensitization, or a combinationthereof that are known for emulsions for the preparation of theconventional light-sensitive materials.

When the sensitizing dyes are added to the silver halide emulsion, thesensitizing dye is preferably added during the preparation of theemulsion. When the organic silver salts are introduced in thelight-sensitive microcapsule, the emulsion of the organic silver saltscan be prepared in the same manner as in the preparation of the silverhalide emulsion.

In the preparation of the light-sensitive material, the polymerizablecompound (the term, "polymerizable compound" includes the photopolymerizable composition and photo polymerizable compound) is used asthe medium for preparation of the liquid composition containing anothercomponent of the light-sensitive layer. For example, the silver halide,(including the silver halide emulsion), the reducing agent, the photopolymerization initiator or the color image forming substance can bedissolved, emulsified or dispersed in the polymerizable compound toprepare the light-sensitive material. Especially, the color imageforming substance is preferably incorporated into the polymerizablecompound. Further, the necessary components for preparation of amicrocapsule, such as shell material can be incorporated into thepolymerizable compound.

The light-sensitive composition which is the polymerizable compoundcontaining the silver halide can be prepared using the silver halideemulsion. The light-sensitive composition can be also prepared usingsilver halide powders which can be prepared by lyophilization. Theselight-sensitive composition can be obtained by stirring thepolymerizable compound and the silver halide using a homogenizer, ablender, a mixer of other conventional stirring device.

Polymers having a principal chain consisting essentially of ahydrocarbon chain substituted in part with hydrophilic groups whichcontain, in their terminal groups, --OH or nitrogen having a loneelectron-pair are preferably introduced into the polymerizable compoundprior to the preparation of the light-sensitive composition. The polymerhas a function of dispersing silver halide or other component in thepolymerizable compound very uniformly as well as a function of keepingthus dispered state. Further, the polymer has another function ofgathering silver halide along the interface between the polymerizablecompound (i.e., light-sensitive composition) and the aqueous medium inpreparation of the microcapsule. Therefore, using this polymer, silverhalide can be easily introduced into the shell material of themicrocapsule.

The light-sensitive composition can be also prepared by dispersingmicrocapsule containing silver halide emulsion as a core structure inthe polymerizable compound instead of employing the above polymer.

Instead of employing the above polymer, the light-sensitive compositioncan be prepared by dispersing the microcapsules having the silver halideemulsion as core material in the emulsion of the polymerizable compound.

The polymerizable compound (including the light-sensitive composition)are preferably emulsified in an aqueous medium to prepare the coatingsolution. The necessary components for preparation of the microcapsule,such as shell material can be incorporated into the emulsion. Further,other components such as the reducing agent can be added to theemulsion. The emulsion of the polymerizable compound can be processedfor forming shell of the microcapsule.

Examples of the process for preparation of the microcapsules include aprocess utilizing coacervation of hydrophilic wall-forming materials asdescribed in U.S. Pat. Nos. 2,800,457 and 2,800,458; an interfacialpolymerization process as described in U.S. Pat. No. 3,287,154, U.K.Patent No. 990,443 and Japanese Patent Publications Nos. 38(1963)-19574,42(1967)-446 and 42(1967)-771; a process utilizing precipitation ofpolymers as described in U.S. Pat. Nos. 3,418,250 and 3,660,304; aprocess of using isocyanate-polyol wall materials as described in U.S.Pat. No. 3,796,669; a process of using isocyanate wall materials asdescribed in U.S. Pat. No. 3,914,511; a process of usingurea-formaldehyde or urea-formaldehyde-resorcinol wall-forming materialsas described in U.S. Pat. Nos. 4,001,140, 4,087,376 and 4,089,802; aprocess of using melamine-formaldehyde resins hydroxypropyl cellulose orlike wall-forming materials as described in U.S. Pat. No. 4,025,455; anin situ process utilizing polymerization of monomers as described inU.K. Patent No. 867,797 and U.S. Pat. No. 4,001,140; an electrolyticdispersion and cooling process as described in U.K. Patent Nos. 952,807and 965,074; a spray-drying process as described in U.S. Pat. No.3,111,407 and U.K. Patent 930,422; in the like. It is preferable, thoughnot limitative, that the microcapsule is prepared by emulsifying corematerials containing the polymerizable compound and forming a polymericmembrane (i.e., shell) over the core materials.

When the emulsion of the polymerizable compound (including thedispersion of the microcapsule) has been prepared by using thelight-sensitive composition, the emulsion can be used as the coatingsolution of the light-sensitive material. The coating solution can bealso prepared by mixing the emulsion of the polymerizable compound andthe silver halide emulsion.

The light-sensitive material of the invention can be prepared by coatingand drying the above-prepared coating solution on a support. The processfor coating the coating solution on a support can be easily carried outin the conventional manner.

Use of the light-sensitive material is described below.

In the use of the light-sensitive material of the invention, adevelopment process is conducted simultaneously with or after animagewise exposure.

Various exposure means can be employed in the imagewise exposure, and ingeneral, the latent image on the silver halide is obtained by imagewiseexposure to radiation including visible light. The type of light sourceand exposure can be selected depending on the light-sensitivewavelengths determined by spectral sensitization or sensitivity ofsilver halide. Original image can be either monochromatic image or colorimage.

A development of the light-sensitive material can be conductedsimultaneously with or after the imagewise exposure. The development canbe conducted using a developing solution in the same manner as the imageforming method described in Japanese Patent Publication No.45(1970)-11149. The image forming method described in Japanese PatentProvisional Publication No. 61(1986)-69062 which employs a heatdevelopment process has an advantage of simple procedures and shortprocessing time because of the dry process. Thus, the latter method ispreferred as the development process of the light-sensitive material.

Heating in the heat development process can be conducted in variousknown manners. The heating layer which is arranged on thelight-sensitive material can be used as the heating means in the samemanner as the light-sensitive material described in Japanese PatentProvisional Publication No. 61(1986)-294434. The light-sensitivematerial is preferably heated while supprissing supply of oxygen intothe light-sensitive layer from outside. Heating temperatures for thedevelopment process usually ranges from 80° C. to 200° C., andpreferably from 100° C. to 160° C. Various heating patterns areapplicable. The heating time is usually not shorter than 1 second,preferably from 1 second to 5 minutes, and more preferably from 5seconds to 1 minute.

During the above development process, a polymerizable compound withinthe area where a latent image of the silver halide has been formed.

A polymer image can be formed on the light-sensitive layer in the aboveprocess. A color image can be obtained by fixing a dye or pigment on apolymer image.

Further, a color image can be formed on the light-sensitive material inwhich the light-sensitive layer contains a color former and a developer,one of them is together with the polymerizable compound contained in amicrocapsule, and the other is arranged outside of the microcapsule.

In the image forming method employing the light-sensitive material, theimage is preferably formed on an image-receiving material. Theimage-receiving material is described hereinbelow.

Examples of the material employable as the support of theimage-receiving material include baryta paper in addition to variousexamples which can be employed as the support of the knownlight-sensitive material. In the case that a porous material, such aspaper is employed as the support of the image-receiving material, theporous support preferably has such a surface characteristic that afiltered maximum waviness of not less than 4 μm is observed in not morethan 20 positions among 100 positions which are determined at random ona filtered waviness curve obtained according to JIS-B-0610. Further, atransparent material can be employed as the support of theimage-receiving material to obtain a transparent or a projected image.

The image-receiving material is usually prepared by providing theimage-receiving layer on the support. The image-receiving layer can beconstructed according to the color formation system. In the cases that apolymer image is formed on the image-receiving material and that a dyeor pigment is employed as the color image forming substance, theimage-receiving material can be composed of a simple support.

For example, when a color formation system using a color former anddeveloper is employed, the developer can be contained in theimage-receiving layer. Further, the image-receiving layer can becomposed of at least one layer containing a mordant. The mordant can beselected from the compounds known in the art of the conventionalphotography according to the kind of the color image forming substance.If desired, the image-receiving layer can be composed of two or morelayers containing two or more mordants different in the mordanting powerfrom each other.

The image-receiving layer preferably contains a polymer as binder. Thebinder which may be employed in the above-mentioned light-receivinglayer is also employable in the image-receiving layer. Further, apolymer having a transmission coefficient of oxygen of not more than1.0×10⁻¹¹ cm³ ·cm/cm² ·sec·cmHg can be used as the binder ro protect thecolor of the image formed on the image-receiving material.

The image-receiving layer can contain a granulated thermoplasticcompound to obtain a glossy image. There is no specific limitation withrespect to the thermoplastic compound. The thermoplastic compoundinclude known plastic resin and wax. The thermoplastic resin preferablyhas a gloss transition temperature of not more than 200° C. The waxpreferably has a melting point of not more than 200° C. Further, a photopolymerization initiator or a thermalpolymerization initiator can becontained in the image-receiving layer to polymerize the unpolymerizedpolymerizable compound.

A dye or pigment can be contained in the image-receiving layer for thepurpose of entering letters, symbols, frames etc. in the image-receivinglayer, or of giving a certain color to the background of the image.Further, the dye or pigment can be also employed for the purpose ofmaking it easy to distinguish the sides of the image-receiving material.In the case that it is possible that the dye or pigment disturbs theimage formed on the image-receiving layer, it is preferred that thedensity of the dye or pigment is low (e.g. reflection density of nothigher than 1), or the dye or pigment has a property of being decoloredwhen it is heated or irradiated with light.

Further, when a white pigment, such as titanium dioxide, barium sulfateetc. is contained in the image-receiving layer, the image-receivinglayer can function as a white reflection layer. In this case, the whitepigment is used in an amount of from 10 g to 100 g based on 1 g of thethermoplastic material.

The above-mentioned dye and pigment can be either uniformly or partiallycontained in the image-receiving layer. For example, when the support iscomposed of transparent material, the white pigment can be partiallycontained in the image-receiving layer to make a part of a reflectionimage to be transparent. Thus, information of the image which isunnecessary in a transparent image can be entered in the part of theimage-receiving layer containing the white pigment as the reflectionimage.

The image-receiving layer can be composed of two or more layersaccording to the above-mentioned functions. The thickness of theimage-receiving layer preferably ranges from 1 to 100 μm, morepreferably from 1 to 20 μm.

A protective layer can be provided on the surface of the image-receivinglayer. A layer containing a granulated thermoplastic compound can bealso provided on the image-receiving layer.

A layer containing an adhesive and a release paper can be provided inthe order on the support of the image-receiving material on the oppositeside of the image-receiving layer.

After the development process, pressing the light-sensitive material incontact with the image-receiving material to transfer the polymerizablecompound which is still polymerizable to the image-receiving material, apolymer image can be obtained in the image-receiving material. Theprocess for pressing can be carried out in various known manners.

In the cases that the light-sensitive layer contains a color imageforming substance, the color image forming substance is fixed bypolymerization of the polymerizable compound. Then, pressing thelight-sensitive material on the image-receiving material to transfer thecolor image forming substance in unfixed portion, a color image can beproduced on the image-receiving material.

After the image is formed on the image-receiving material, theimage-receiving material can be heated to polymerize the transferredunpolymerized polymerizable compound. By the above-mentioned process,the obtained image can be improved in the preservability.

Various image recording apparatus can be used for the image-receivingmethod. An example of the apparatus comprises an exposure device forimagewise exposing the light-sensitive material to form a latent image,a heat development device for fixing the area corresponding to thelatent image, a transfer device for pressing the developedlight-sensitive material on the image-receiving material. Anotherexample of the apparatus comprises an fixing apparatus for irradiatingwith light, pressing or heating the image-receiving material on which animage has been transferred in addition to the above-mentioned devices.

The light-sensitive material can be used for monochromatic or colorphotography, printing, radiography, diagnosis (e.g., CRT photography ofdiagnostic device using supersonic wave), copy (e.g., computer-graphichard copy), etc.

The present invention is further described by the following exampleswithout limiting the invention.

EXAMPLE 1 Preparation of Silver Halide Emulsion

In 3,000 ml of water were dissolved 40 g of gelatin and 23.8 g ofpotassium bromide, and the resulting gelatin solution was kept at 50° C.To the gelatin solution, 200 ml of an aqueous solution containing 34 gof silver nitrate was added over a period of 10 minutes while stirring.To the solution, 100 ml of aqueous solution containing 3.3 g ofpotassium iodide was added over a period of 2 minutes. After theemulsion was adjusted to a pH for sedimentation, excess salts wereremoved. The emulsion was adjusted to a pH of 6.0 to obtain a silveriodobromide emulsion. The yield of the emulsion was 400 g.

Preparation of Silver Benzotriazole Emulsion

In 3,000 ml of water were dissolved 28 g of gelatin and 13.2 g ofbenzotriazole, and the resulting gelatin solution was kept at 40° C. Tothe gelatin solution, 100 ml of an aqueous solution containing 17 g ofsilver nitrate was added over a period of 2 minutes while stirring.After the emulsion was adjusted to a pH for sedimentation, excess saltswere removed. The emulsion was adjusted to a pH of 6.3 to obtain asilver benzotriazole emulsion. The yield of the emulsion was 400 g.

Preparation of Light-Sensitive Composition

In 100 g of trimethylolpropane triacrylate were dissolved 0.40 g of thefollowing copolymer, 6.00 g of Pargascript Red I-6-B (tradename ofCiba-Geigy) and 2 g of Emulex NP-8 (tradename of Nippon Emulsion Co.,Ltd.). ##STR8##

In 18.00 g of the resulting solution was dissolved 0.002 g of thefollowing thiol derivative. To the solution was further added a solutionin which 1.22 g of the following reducing agent (1) and 1.29 g of thefollowing hydrazine derivative (H-1) were dissolved in 1.80 g ofmethylene chloride. ##STR9##

Further, to the resulting mixture were added 3.5 g of the silver halideemulsion and 3.35 g of the silver benzotriazole emulsion, and themixture was stirred at 15,000 r.p.m. for 5 minutes in a homogenizer toobtain a light-sensitive composition.

Preparation of Light-Sensitive Microcapsule

To 10.51 g of 18.6% aqueous solution of Isobam (tradename of KurarayCo., Ltd.) was added 48.56 g of 2.89% aqueous solution of pectin. Afterthe solution was adjusted to a pH of 4.0 using 10% sulfuric acid, thelight-sensitive composition was added to the resulting solution, and themixture was stirred at 7,000 r.p.m. for 2 minutes to emulsify thelight-sensitive composition in the aqueous medium.

To 72.5 g of the aqueous emulsion were added 8.32 g of 40% aqueoussolution of urea, 2.82 g of 11.3% aqueous solution of resorcinol, 8.56 gof 37% aqueous solution of formaldehyde and 2.74 g of 8.76% aqueoussolution of ammonium sulfate in this order, and the mixture was heatedat 60° C. for 2 hours while stirring. After the mixture was adjusted toa pH of 7.0 using 10% aqueous solution of sodium hydroxide, 3.62 g of30.9% aqueous solution of sodium hydrogen sulfite was added to themixture to obtain a dispersion containing light-sensitive microcapsules.

Preparation of Light-Sensitive Material

To 10.0 g of the light-sensitive microcapsule dispersion were added 1.0g of 10% aqueous solution of the following anionic surfactant and 1.0 gof 10% solution (solvent: water/ethanol=50/50 as volume ratio) ofguanidine trichroloacetate to prepare a coating solution. The coatingsolution was uniformly coated on a polyethylene terephthalate film(thickness: 100 μm) using a coating rod of #40 to give a layer having awet thickness of 70 μm and dried at about 40° C. to obtain alight-sensitive material (A). ##STR10##

EXAMPLE 2

A light-sensitive material (B) was prepared in the same manner as inExample 1 except that 1.28 g of the following hydrazine derivative (H-9)was used in place of the hydrazine derivative (H-1). ##STR11##

COMPARISON EXAMPLE 1

A light-sensitive material (C) was prepared in the same manner as inExample 1 except that the following reducing agent (x) was used in placeof the reducing agent (1). ##STR12##

COMPARISON EXAMPLE 2

A light-sensitive material (D) was prepared in the same manner as inExample 2 except that the reducing agent (x) was used in place of thereducing agent (1).

COMPARISON EXAMPLE 3

A light-sensitive material (E) was prepared in the same manner as inExample 1 except that the following reducing agent (y) was used in placeof the reducing agent (1). ##STR13##

Preparation of Image-Receiving Material

To 150 g of water was added 11 g of 40% aqueous solution of sodiumhexametaphosphate, and were further added 34 g of zinc3,5-di-α-methylbenzylsalicylate and 82 g of 55% slurry of calciumcarbonate, followed by coarsely dispersing in a mixer. The coarsedispersion was then finely dispersed in Dynomill dispersing device. To200 g of the resulting dispersion were added 6 g of 50% latex of SBR(styrene-butadiene rubber) and 55 g of 8% aqueous solution of polyvinylalcohol, and the resulting mixture was made uniform.

The mixture was then uniformly coated on an art paper having a basisweight of 43 g/m² to give a layer having a wet thickness of 30 μm anddried to obtain an image-receiving material.

Evaluation of Light-Sensitive Material

Each of the light-sensitive materials (A) to (E) prepared in Examples 1and 2 and Comparison Examples 1 to 3 was imagewise exposed to lightusing a halogen lamp at 2,000 lux for 1 second and then heated on a hotplate at 125° C. for 30 seconds. Each of the exposed and heatedlight-sensitive materials was then combined with the image-receivingmaterial and passed through press rolls a pressure of 350 kg/cm² toobtain a magenta positive image on the image receiving material. Thedensity of the obtained image was measured using Macbeth reflectiondensitometer.

The results are set forth in Table 1. In Table 1, each of thelight-sensitive material is evaluated as the value of the contrast ofthe image. The contrast means the ratio of the maximum density to theminimum density in the obtained image.

                  TABLE 1                                                         ______________________________________                                        Light-sensitive                                                                           Reducing   Hydrazine Contrast                                     Material    Agent      Derivative                                                                              in Image                                     ______________________________________                                        (A)         (1)        (H-1)     13                                           (B)         (1)        (H-9)     12.5                                         (C)         (x)        (H-1)     5.0                                          (D)         (x)        (H-9)     4.8                                          (E)         (y)        (H-1)     1.1                                          ______________________________________                                    

It is apparent from the results in Table 1 that each of thelight-sensitive materials using the reducing agent of the presentinvention forms an improved clear positive image in which the contrastis very high.

We claim:
 1. A light-sensitive material comprising a support and alight-sensitive layer containing silver halide, a polymerizablecompound, a hydrazine derivative and a reducing agent of formula (I),said silver halide, polymerizable compound, hydrazine derivative andreducing agent being contained in microcapsules which are dispersed inthe light-sensitive layer: ##STR14## in which each of Ar¹ and Ar²independently is an aryl group, which may have one or more substituentgroups; and each of R¹, R² and R³ independently is a monovalent groupselected from the group consisting of hydrogen, a halogen atom, an alkylgroup, a cycloalkyl group, an aralkyl group, an aryl group, an alkenylgroup, an alkynyl group, a heterocyclic group, an alkoxy group, analkylthio group and an acylamino group, each of which may have one ormore substituent groups.
 2. The light-sensitive material as claimed inclaim 1, wherein each of Ar¹ and Ar² in the formula (I) is phenyl, whichmay have one or more substituent groups.
 3. The light-sensitive materialas claimed in claim 1, wherein each of Ar¹ and Ar² in the formula (I)independently has one or more substituent groups which are selected fromthe group consisting of an alkyl group, a halogen atom, an alkoxy group,an alkylamino group, an acylamino group, an alkylsulfonylamino group, analkylsulfamoyl group and alkylcarbamoyl group.
 4. The light-sensitivematerial as claimed in claim 1, wherein each of R¹, R² and R³ in theformula (I) independently is a monovalent group selected from the groupconsisting of hydrogen, a halogen atom, an alkyl group and an acylaminogroup, which may have one or more substituent groups.
 5. Thelight-sensitive material as claimed in claim 1, wherein each of R¹, R²and R³ in the formula (I) is hydrogen.
 6. The light-sensitive materialas claimed in claim 1, wherein a color image forming substance iscontained in the light-sensitive layer.
 7. The light-sensitive materialas claimed in claim 1, wherein the polymerizable compound is a compoundhaving an ethylenic unsatulated group.
 8. The light-sensitive materialas claimed in claim 1, wherein a base or base precursor is contained inthe light-sensitive layer.
 9. The light-sensitive material as claimed inclaim 1, wherein the reducing agent having the formula (I) is containedin an amount of from 0.1 to 1,500 mole % based on the total silvercontent in the light-sensitive layer.